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                     Secunia Research 27/07/2006

     - Mozilla Firefox XPCOM Event Handling Memory Corruption -

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Table of Contents

Affected Software....................................................1
Severity.............................................................2
Vendor's Description of Software.....................................3
Description of Vulnerability.........................................4
Solution.............................................................5
Time Table...........................................................6
Credits..............................................................7
References...........................................................8
About Secunia........................................................9
Verification........................................................10

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1) Affected Software 

Mozilla Firefox 1.5.0.1, 1.5.0.2, 1.5.0.3, and 1.5.0.4.

NOTE: Other versions may also be affected.

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2) Severity 

Rating: Highly critical
Impact: System access
Where:  Remote

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3) Vendor's Description of Software 

"The award-winning, free Web browser is better than ever. Browse the
Web with confidence - Firefox protects you from viruses, spyware and
pop-ups. Enjoy improvements to performance, ease of use and privacy.
It's easy to import your favorites and settings and get started."

Product Link:
http://www.mozilla.com/firefox/ 

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4) Description of Vulnerability

Secunia Research has discovered a vulnerability in Mozilla Firefox,
which can be exploited by malicious people to compromise a vulnerable
system.

The vulnerability is caused due to an memory corruption error within
the handling of simultaneously happening XPCOM events resulting in the
use of a deleted timer object.

Successful exploitation allows execution of arbitrary code.

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5) Solution 

Update to version 1.5.0.5.

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6) Time Table 

22/06/2006 - Vendor notified.
23/06/2006 - Vendor response.
27/07/2006 - Public disclosure.

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7) Credits 

Discovered by Carsten Eiram, Secunia Research.

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8) References

Mozilla.org:
http://www.mozilla.org/security/announce/2006/mfsa2006-46.html 

The Common Vulnerabilities and Exposures (CVE) project has assigned 
CVE-2006-3113 for the vulnerability.

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9) About Secunia 

Secunia collects, validates, assesses, and writes advisories regarding 
all the latest software vulnerabilities disclosed to the public. These 
advisories are gathered in a publicly available database at the 
Secunia website:

http://secunia.com/ 

Secunia offers services to our customers enabling them to receive all 
relevant vulnerability information to their specific system 
configuration. 

Secunia offers a FREE mailing list called Secunia Security Advisories: 

http://secunia.com/secunia_security_advisories/ 

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10) Verification 

Please verify this advisory by visiting the Secunia website:
http://secunia.com/secunia_research/2006-53/ 

Complete list of vulnerability reports published by Secunia Research:
http://secunia.com/secunia_research/ 

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